ext4: Convert ext4_lock_group to use sb_bgl_lock

We have sb_bgl_lock() and ext4_group_info.bb_state
bit spinlock to protech group information. The later is only
used within mballoc code. Consolidate them to use sb_bgl_lock().
This makes the mballoc.c code much simpler and also avoid
confusion with two locks protecting same info.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 14 insertions, 15 deletions

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 916d05c881ca..82f7d1d7eae0 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -122,16 +122,16 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
                 unlock_buffer(bh);
                 return bh;
         }
-        spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
+        ext4_lock_group(sb, block_group);
         if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
                 ext4_init_inode_bitmap(sb, bh, block_group, desc);
                 set_bitmap_uptodate(bh);
                 set_buffer_uptodate(bh);
-                spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group));
+                ext4_unlock_group(sb, block_group);
                 unlock_buffer(bh);
                 return bh;
         }
-        spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group));
+        ext4_unlock_group(sb, block_group);
         if (buffer_uptodate(bh)) {
                 /*
                  * if not uninit if bh is uptodate,
@@ -246,9 +246,8 @@ void ext4_free_inode(handle_t *handle, struct inode *inode)
                 goto error_return;
 
         /* Ok, now we can actually update the inode bitmaps.. */
-        spin_lock(sb_bgl_lock(sbi, block_group));
-        cleared = ext4_clear_bit(bit, bitmap_bh->b_data);
-        spin_unlock(sb_bgl_lock(sbi, block_group));
+        cleared = ext4_clear_bit_atomic(ext4_group_lock_ptr(sb, block_group),
+                                        bit, bitmap_bh->b_data);
         if (!cleared)
                 ext4_error(sb, "ext4_free_inode",
                            "bit already cleared for inode %lu", ino);
@@ -260,7 +259,7 @@ void ext4_free_inode(handle_t *handle, struct inode *inode)
                 if (fatal) goto error_return;
 
                 if (gdp) {
-                        spin_lock(sb_bgl_lock(sbi, block_group));
+                        ext4_lock_group(sb, block_group);
                         count = ext4_free_inodes_count(sb, gdp) + 1;
                         ext4_free_inodes_set(sb, gdp, count);
                         if (is_directory) {
@@ -276,7 +275,7 @@ void ext4_free_inode(handle_t *handle, struct inode *inode)
                         }
                         gdp->bg_checksum = ext4_group_desc_csum(sbi,
                                                         block_group, gdp);
-                        spin_unlock(sb_bgl_lock(sbi, block_group));
+                        ext4_unlock_group(sb, block_group);
                         percpu_counter_inc(&sbi->s_freeinodes_counter);
                         if (is_directory)
                                 percpu_counter_dec(&sbi->s_dirs_counter);
@@ -707,10 +706,10 @@ static int find_group_other(struct super_block *sb, struct inode *parent,
 
 /*
  * claim the inode from the inode bitmap. If the group
- * is uninit we need to take the groups's sb_bgl_lock
+ * is uninit we need to take the groups's ext4_group_lock
  * and clear the uninit flag. The inode bitmap update
  * and group desc uninit flag clear should be done
- * after holding sb_bgl_lock so that ext4_read_inode_bitmap
+ * after holding ext4_group_lock so that ext4_read_inode_bitmap
  * doesn't race with the ext4_claim_inode
  */
 static int ext4_claim_inode(struct super_block *sb,
@@ -721,7 +720,7 @@ static int ext4_claim_inode(struct super_block *sb,
         struct ext4_sb_info *sbi = EXT4_SB(sb);
         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 
-        spin_lock(sb_bgl_lock(sbi, group));
+        ext4_lock_group(sb, group);
         if (ext4_set_bit(ino, inode_bitmap_bh->b_data)) {
                 /* not a free inode */
                 retval = 1;
@@ -730,7 +729,7 @@ static int ext4_claim_inode(struct super_block *sb,
         ino++;
         if ((group == 0 && ino < EXT4_FIRST_INO(sb)) ||
                         ino > EXT4_INODES_PER_GROUP(sb)) {
-                spin_unlock(sb_bgl_lock(sbi, group));
+                ext4_unlock_group(sb, group);
                 ext4_error(sb, __func__,
                            "reserved inode or inode > inodes count - "
                            "block_group = %u, inode=%lu", group,
@@ -779,7 +778,7 @@ static int ext4_claim_inode(struct super_block *sb,
         }
         gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
 err_ret:
-        spin_unlock(sb_bgl_lock(sbi, group));
+        ext4_unlock_group(sb, group);
         return retval;
 }
 
@@ -935,7 +934,7 @@ got:
                 }
 
                 free = 0;
-                spin_lock(sb_bgl_lock(sbi, group));
+                ext4_lock_group(sb, group);
                 /* recheck and clear flag under lock if we still need to */
                 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
                         free = ext4_free_blocks_after_init(sb, group, gdp);
@@ -944,7 +943,7 @@ got:
                         gdp->bg_checksum = ext4_group_desc_csum(sbi, group,
                                                                 gdp);
                 }
-                spin_unlock(sb_bgl_lock(sbi, group));
+                ext4_unlock_group(sb, group);
 
                 /* Don't need to dirty bitmap block if we didn't change it */
                 if (free) {